JP2009093913A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device having a highly reliable display quality with a long life by applying a gas adsorbent capable of fixing and removing moisture and oxygen in a sealing space of an electroluminescent member in a display device, and preventing separation of interface of the electrode and a luminous layer due to the moisture and oxygen, and high resistance by oxidation of the electrode or deterioration of the luminous layer itself. <P>SOLUTION: The display device is provided with an organic electroluminescent element consisting of a substrate 6, an organic electroluminescent member 5 installed on the substrate, and a sealing member 7 to seal the substrate 6 and the organic electroluminescent member 5, and is equipped with a gas adsorbent 8 containing at least ZSM-5 type zeolite which is copper ion exchanged in the internal space of the sealing member 7. Since the gas adsorbent 8 can fix and remove moisture and oxygen up to be in a lower partial pressure region than a conventional existing adsorbent, and a display device having superior reliability and high performance can be provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a display device using an organic electroluminescence element.

  2. Description of the Related Art In recent years, organic electroluminescence display devices that can display thin, light, and high-quality images have attracted attention as display devices that replace CRTs and liquid crystal display devices.

  An organic electroluminescent element has a structure in which an organic light emitting material layer is sandwiched between a pair of counter electrodes. Electrons from one electrode and holes from the other electrode are injected into the light emitting material layer, so The holes combine to emit light.

  However, the organic electroluminescence element has low resistance to foreign matters such as moisture, and the luminance and uniformity of light emission may be significantly lowered when driven for a long time. This is because defects such as peeling of the interface between the electrode and the light-emitting layer, high resistance due to oxidation of the electrode, or alteration of the light-emitting layer itself are caused by the influence of moisture or oxygen.

  For this reason, a technique is disclosed in which an adsorbent having a property of adsorbing moisture or the like is installed near the organic electroluminescence element to avoid deterioration of the organic electroluminescence element due to moisture or the like.

  For example, a technique is disclosed in which a porous hygroscopic sheet composed of an organic binder resin and a hygroscopic adsorbent is disposed in the vicinity of the organic electroluminescence structure and the deterioration is effectively prevented by adsorbing moisture (patent) Reference 1).

As the hygroscopic material, a chemical adsorbent is effective, and a material selected from alkali metal oxides, alkaline earth metal oxides, metal sulfates and halides is disclosed. For example, barium oxide is said to be able to realize a moisture content of 7 × 10 ⁻⁴ g / m ^3, and can be said to be able to maintain a very excellent dry state.

In addition, for example, a technique is disclosed that includes a desiccant made of a porous inorganic material in a sealed space that covers an electroluminescence element (see Patent Document 2). Zeolite and the like are effective as a porous inorganic material.
JP 2002-280166 A JP 2003-157969 A

  However, the adsorbents selected from alkali metal oxides, alkaline earth metal oxides, metal sulfates and halides exemplified in Patent Document 1 include those that are difficult to handle.

  For example, when water is adsorbed, the volume increases greatly, and barium oxide that requires measures to prevent scattering in the sealed space is necessary. Such as reduced calcium oxide. On the other hand, sodium sulfate and calcium sulfate, which are metal sulfates, have weak hygroscopicity.

  Also included are those that are harmful to the environment. As an example, barium oxide has toxicity, is a deleterious substance subject to the Poisonous and Deleterious Substances Control Law, and is also a PRTR Law Class 1 Designated Chemical Substance. Since it is used inside the organic electroluminescence element, it does not directly affect the human body. However, considering future recycling and the like, a harmless material is considered to be preferable.

  Moreover, since these materials cannot adsorb oxygen, it is necessary to separately apply an oxygen adsorbing material.

  In addition, the inorganic porous material such as zeolite exemplified in Patent Document 2 can adsorb a certain amount of moisture and oxygen. However, when manufacturing a display device using an organic electroluminescence element, dry nitrogen gas having a dew point of about −80 ° C. is enclosed.

  The saturated water vapor pressure at a dew point of −80 ° C. is 0.00041 torr (0.054 Pa). In order to adsorb moisture under this low partial pressure, zeolite is inferior in hygroscopicity to chemical adsorbents. The same is true for oxygen adsorption.

  That is, since the remaining moisture and oxygen may cause a problem that impairs long-term reliability, an adsorbent capable of removing moisture and oxygen with higher purity is desired.

  The object of the present invention is not harmful to the environment, suppresses deterioration of luminance and chromaticity of light emission and chromaticity caused by moisture and oxygen in the sealing space of the electroluminescence element, and changes over time, and has a long life and high reliability. It is to provide a display device having quality.

  In order to achieve the above object, the display device of the present invention includes a gas adsorbent containing at least a copper ion exchanged ZSM-5 type zeolite in a sealed space in which an organic electroluminescence member is sealed.

  Copper ion exchanged ZSM-5 type zeolite can adsorb moisture and oxygen with a strong chemisorbing adsorption force even under a very low partial pressure, and can immobilize and remove moisture and oxygen. . In the present invention, the gas adsorbent provided in the sealed space in which the organic electroluminescent member is sealed contains at least copper ion-exchanged ZSM-5 type zeolite, and a low content in the sealed space of the electroluminescent member. Since moisture under pressure can be adsorbed and removed, deterioration of emission luminance and chromaticity caused by moisture and oxygen in the sealed space of the electroluminescent member and aging change are suppressed, and long-life and reliable display quality is provided. A display device can be provided.

  Copper ion exchanged ZSM-5 type zeolite can adsorb moisture and oxygen with a strong chemisorbing adsorption force even under a very low partial pressure, and can immobilize and remove moisture and oxygen. . Moreover, although it is accompanied by chemisorption, it does not generate a compound such as an alkali metal oxide, so that volume expansion and accompanying scattering do not occur. That is, an organic electroluminescence display device is provided with a copper ion-exchanged ZSM-5 type zeolite adsorbent having both chemical adsorption characteristics that realize strong adsorption and physical adsorption characteristics that do not cause alteration of the adsorbent. This makes it possible to prevent peeling of the interface between the electrode and the light emitting layer due to moisture and oxygen, high resistance due to oxidation of the electrode, or alteration of the light emitting layer itself, and to maintain the luminance and uniformity of light emission, A long-life and reliable display quality can be obtained.

  The invention of the display device according to claim 1 of the present invention is characterized in that a gas adsorbent containing at least copper ion exchanged ZSM-5 type zeolite is provided in a sealed space in which an organic electroluminescence member is sealed. It is what.

  Copper ion exchanged ZSM-5 type zeolite is known for its high activity against gas adsorption. In general, zeolite is a physically adsorbing substance due to its three-dimensional porous structure, but ZSM-5 type zeolite that has been subjected to copper ion exchange exhibits behavior similar to that of chemical adsorption of copper ions introduced by ion exchange. It is thought to be because.

  Actually, when the gas adsorption curve is measured, it can be confirmed that the ZSM-5 type zeolite subjected to the copper ion exchange has a clear difference in adsorption amount between the primary adsorption and the secondary adsorption, and has a chemical adsorption property.

  In addition, ZSM-5 type zeolite exchanged with copper ions has been reported to adsorb nitrogen as well, but when compared to moisture and oxygen, moisture and oxygen show stronger adsorption, so there are some active sites. However, once nitrogen is adsorbed, it is replaced with thermodynamically stable moisture and oxygen, and finally moisture and oxygen are immobilized and removed.

  By containing ZSM-5 type zeolite exchanged with copper ions as a gas adsorbent in the display device, moisture and oxygen components at a low partial pressure are adsorbed and removed. As a result, the electrode and the light emitting layer are caused by moisture and oxygen. It is possible to prevent peeling of the interface, increase in resistance due to oxidation of the electrode, or alteration of the light emitting layer itself, and the luminance and uniformity of light emission can be maintained, and a long-life and reliable display quality can be obtained.

  The production of the ZSM-5 type zeolite subjected to the copper ion exchange is performed through a process of copper ion exchange, washing with water, drying and heat treatment of a commercially available ZSM-5 type zeolite.

Copper ion exchange can be performed by a known method, but a method of immersing in an aqueous solution of a soluble salt of copper, such as an aqueous solution of copper chloride or an aqueous solution of copper ammine, is generally used, particularly copper (II) propionate or acetic acid. Those prepared by a method using a Cu ²⁺ solution containing carboxylate such as copper (II) have high chemisorption activity.

  Wash with water thoroughly after ion exchange.

  Next, heat drying or drying under reduced pressure is performed to remove surface adhering water.

Thereafter, an appropriate heat treatment is performed under a low pressure. This is necessary to reduce Cu ²⁺ introduced by ion exchange to Cu ⁺ and develop chemical adsorption ability. The pressure during the heat treatment is 10 mPa or less, preferably 1 mPa or less, and the temperature is about 300 ° C. or more, preferably about 500 ° C. to 600 ° C. in order to promote the reduction to Cu ⁺ .

  Through the above process, the copper ion exchanged ZSM-5 type zeolite provided with gas adsorption activity has gas adsorption activity with chemical adsorption properties.

  Further, when the copper ion exchanged ZSM-5 type zeolite having gas adsorption activity is handled in the atmosphere, the atmospheric components are adsorbed and deactivated. Therefore, after activation by heat treatment, it is necessary to handle under high vacuum or in an inert gas, and when applied to a display device, the copper ion exchange ZSM-5 type zeolite does not directly contact the air, and optionally vents. You may enclose in the device which expresses sex.

  Moreover, pelletization, shaping | molding, etc. may be given when handling copper ion exchange ZSM-5 type zeolite as a gas adsorbent.

In the copper ion exchanged ZSM-5 type zeolite, copper is first ion exchanged as Cu ²⁺ . Next, by performing an appropriate heat treatment under low pressure, Cu ²⁺ is reduced to Cu ⁺ and exhibits gas adsorption activity.

Therefore, regarding the silica to alumina ratio of the ZSM-5 type zeolite, when the silica to alumina ratio is low, that is, when a large amount of −1 valent aluminum is present, Cu ²⁺ is more stable, and heat treatment makes Cu ⁺ become Cu ⁺ . Since the sites to be reduced are reduced, the chemisorption activity is also reduced.

On the other hand, when the silica to alumina ratio is large, i.e., when there is little −1 valent aluminum, less copper is introduced by ion exchange and thus less Cu ⁺ sites, which also reduces chemisorption activity.

  Therefore, in order to express chemisorption activity, it is desirable that the silica to alumina ratio is in an appropriate range, and in the present invention, it is determined that a range of 8 to 25 is appropriate.

  Moreover, the copper ion exchange ZSM-5 type zeolite has no harmful information and has a low environmental load. Moreover, since it is chemical adsorption in the porous inorganic material, there is no increase in volume due to moisture and oxygen adsorption and no scattering into the sealed space.

  The invention of the display device according to claim 2 of the present invention is the invention according to claim 1, wherein at least 60% or more of the copper sites of the ZSM-5 type zeolite sites subjected to copper ion exchange are copper. It is a monovalent site.

  The copper ion exchanged ZSM-5 type zeolite reported so far is ion-exchanged with an aqueous solution of a soluble salt of copper, such as an aqueous solution of copper chloride, an aqueous solution of copper ammine, or an aqueous solution of copper acetate, and then heat-treated. As a result, the copper ions were reduced to monovalent and were given chemisorption activity. The maximum ratio of the chemisorption active copper monovalent sites in the copper sites of the ZSM-5 type zeolite exchanged with copper ions thus synthesized was about 50%.

  In the present invention, ZSM-5 type zeolite, which is excellent in gas adsorption capacity in a low partial pressure region and in which at least 60% or more copper sites exist as adsorption-active copper monovalent sites, is applied as a gas adsorbent. By doing so, it is possible to adsorb moisture and oxygen having a further enhanced adsorption activity under a low partial pressure. As a result, it becomes possible to prevent peeling of the interface between the electrode and the light emitting layer due to moisture and oxygen, increase in resistance due to oxidation of the electrode, or alteration of the light emitting layer itself, and maintain the luminance and uniformity of light emission, A long-life and reliable display quality can be obtained.

  The ratio of copper monovalent sites in the copper ion-exchanged copper sites is one in the copper ion-exchanged ZSM-5 type zeolite with respect to the total amount of copper in the copper ion-exchanged ZSM-5 type zeolite. It is obtained by calculating the carbon oxide adsorption molar amount.

  In addition, the total copper molar amount in the ZSM-5 type zeolite exchanged with copper ions was determined by dissolving the ZSM-5 type zeolite exchanged with copper ion with perchloric acid, etc., and using an ICP emission spectrometer or EDTA titration. It is possible to ask.

  The invention of the display device according to claim 3 of the present invention is the invention according to claim 1 or 2, wherein at least 60% or more of the copper monovalent sites are oxygen tricoordinate copper monovalent sites. It is characterized by.

  Among the copper monovalent sites, it has been clarified that the oxygen tricoordinate copper monovalent site has a stronger interaction with gas molecules and can chemisorb gas. Therefore, it is possible to increase the chemical adsorption capacity for adsorbing moisture and oxygen more firmly under a low partial pressure by using at least 60% of the copper monovalent sites as oxygen tricoordinate copper monovalent sites. It becomes.

  As a result, it becomes possible to prevent peeling of the interface between the electrode and the light emitting layer due to moisture and oxygen, increase in resistance due to oxidation of the electrode, or alteration of the light emitting layer itself, and maintain the luminance and uniformity of light emission, A long-life and reliable display quality can be obtained.

  In addition, among the copper monovalent sites, the ratio of oxygen tricoordinated copper monovalent sites is calculated by calculating the number of moles of chemical adsorption relative to the amount of carbon monoxide adsorbed in the ZSM-5 type zeolite subjected to copper ion exchange. Desired.

  A display device according to a fourth aspect of the present invention is the display device according to any one of the first to third aspects, wherein the ZSM-5 type zeolite subjected to copper ion exchange contains at least copper ions and a buffer. It is characterized by being ion-exchanged with an ion-exchange solution containing ions having an action.

  With this configuration, when the copper ions are exchanged into the ZSM-5 type zeolite, the ions having the buffering action have the action of promoting the reduction of the copper ions. The adsorption capacity in the low partial pressure region increased.

  In addition, when copper ions are exchanged into ZSM-5 type zeolite, the ions that have a buffering action also have the action of introducing copper ions into oxygen tricoordinate sites, so that the gas can be adsorbed more firmly. An increase in adsorption capacity can be obtained.

  As a result, it is possible to strongly adsorb, immobilize and remove a larger volume of moisture and oxygen at a lower partial pressure than existing gas adsorbents, peel off the interface between the electrode and the light emitting layer due to moisture and oxygen, and oxidize the electrode. Therefore, it is possible to prevent the resistance from being increased or the deterioration of the light emitting layer itself, and to maintain the luminance and uniformity of light emission, and to obtain a long-life and reliable display quality.

  Here, the ion having a buffering action refers to an ion having an action of buffering the dissociation equilibrium of a solution containing copper ions.

  For example, the ion dissociation behavior in an aqueous copper acetate solution is shown in (Chemical Formula 1).

To this system, an anion having an appropriate buffer action, for example,
Is added, the equilibrium proceeds to the center of the formula, where monovalent ions containing associated species with acetate
Is stable. Thereby, it became clear that the ratio of the copper monovalent site and the ratio of the oxygen tricoordinate copper monovalent site increased.

  The details of this factor are unknown, but probably the position of the chemisorption active ion exchange site and the shape selectivity due to the relative relationship, such as the steric hindrance of its pore size and ion size, and the 3D structure It is thought to be due to specificity.

  According to a fifth aspect of the present invention, there is provided a display device according to the fourth aspect, wherein the ions having a buffering action are acetate ions.

  With this configuration, since the acetate ion having a buffering action has an action of effectively introducing copper ions into a site that is easily reduced to a monovalent, the ratio of the copper monovalent site is increased, and as a result, the gas An increase in the amount of adsorption can be obtained.

  In addition, when copper ions are exchanged into ZSM-5 type zeolite, acetate ions having a buffer function also have an action of introducing copper ions into oxygen tricoordinate sites, so that gas is more strongly adsorbed. An increase in chemisorption capacity is obtained.

  As a result, it is possible to more strongly adsorb and immobilize moisture and oxygen of a larger volume under a lower partial pressure than existing gas adsorbents, and to peel off the interface between the electrode and the light emitting layer, to increase resistance by oxidizing the electrode, Alternatively, deterioration of the light emitting layer itself can be prevented, luminance and uniformity of light emission can be maintained, and long-life and reliable display quality can be obtained.

  A display device according to a sixth aspect of the present invention is the display device according to the fourth or fifth aspect, wherein the ions having a buffering action are generated from ammonium acetate.

  With this configuration, the copper-ammonium ion-associated species generated by the addition of ammonium acetate is advantageous for ion exchange to the three-coordinate site from the viewpoint of size, and has an action of enhancing gas adsorption activity.

  Furthermore, it has been clarified that ammonium ions are preferentially ion-exchanged over copper to sites that are oxygen two-coordinated, so that the effect that copper ions are selectively ion-exchanged to three-coordinated sites is effective. can get.

  In addition, ammonium ion, which is a counter anion of acetate ion acting as a buffer, has the advantage of desorbing as ammonia during reduction by heating and promoting the reduction of copper, but remains in the ZSM-5 type zeolite base material. Does not adversely affect gas adsorption.

  Therefore, for example, compared to the case where sodium acetate having the same acetate ion is added, the gas adsorption amount under a low partial pressure and the copper ion-exchanged ZSM-5 type having a high ratio of copper monovalent and oxygen tricoordination sites. Zeolite is obtained.

  As a result, it is possible to more strongly adsorb and immobilize moisture and oxygen of a larger volume under a lower partial pressure than existing gas adsorbents, and to peel off the interface between the electrode and the light emitting layer, to increase resistance by oxidizing the electrode, Alternatively, deterioration of the light emitting layer itself can be prevented, luminance and uniformity of light emission can be maintained, and long-life and reliable display quality can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a flowchart showing a method for producing a gas adsorbent containing ZSM-5 type zeolite subjected to copper ion exchange in Embodiment 1 of the present invention.

  In the embodiment of the present invention, the production of the gas adsorbent containing the ZSM-5 type zeolite subjected to the copper ion exchange is performed by an ion exchange step (STEP 1) using an ion exchange solution containing copper ions and ions having a buffer action. ), A washing step (STEP 2) for washing the ZSM-5 type zeolite exchanged with copper ions, a drying step (STEP 3), and a heat treatment step (STEP 4) for reducing copper ions.

  In the ion exchange step (STEP 1), aqueous solutions of existing compounds such as copper acetate, copper propionate, and copper chloride can be used as a solution containing copper ions. For this purpose, copper acetate is desirable.

  In addition, as ions having a buffering action, ions having an action of buffering the ion dissociation equilibrium of a solution containing copper ions, such as acetate ions and propionate ions, can be used, but large capacity adsorption in a low partial pressure region is realized. For this purpose, acetate ions are desirable, and acetate ions derived from ammonium acetate are more desirable.

  An ion exchange solution containing copper ions and ions having a buffering action may be prepared after a solution containing each ion is prepared in advance and then mixed, or each solute may be dissolved in the same solvent.

The number of ion exchanges, the concentration of the copper ion solution, the concentration of the buffer solution, the ion exchange time, the temperature, etc. are not particularly limited, but the ion exchange rate is excellent in the range of 100% to 180%. Indicates. More preferably, it is in the range of 110% to 170%. The ion exchange rate shown here is a calculated value based on the premise that Cu ²⁺ is exchanged per two Na ^{+ s} . When copper is exchanged as Cu ⁺ , the calculation exceeds 100%. Is done.

  In the washing step (STEP 2), it is desirable to wash with distilled water. In the drying step (STEP 3), it is desirable to dry under conditions of less than 100 ° C., and vacuum drying at room temperature may be used.

In the heat treatment step (STEP 4), it is desirable to perform heat treatment at a temperature of 300 ° C. or higher and 800 ° C. or lower under reduced pressure, preferably under a condition of less than 10 ⁻² Pa. The heat treatment time depends on the amount of ZSM-5 type zeolite exchanged with copper ions, but a sufficient time is required to reduce the copper ions from divalent to monovalent. Moreover, if it is 300 degrees C or less, there exists a possibility that the reduction | restoration to monovalence may become inadequate, and if it is 800 degrees C or more, there exists a possibility that the structure of a zeolite may be destroyed. More preferably, it is about 500 ° C to 600 ° C.

  The adsorbent made of ZSM-5 type zeolite exchanged with copper ions in this way can adsorb and immobilize a larger amount of moisture and oxygen more firmly under a lower partial pressure than existing gas adsorbents. It is possible to prevent the peeling of the interface between the electrode and the light emitting layer, the increase in resistance due to the oxidation of the electrode, or the alteration of the light emitting layer itself, maintaining the luminance and uniformity of the light emission, long life and reliable display. Quality can be obtained.

  Moreover, at least 60% or more of the copper sites of the ZSM-5 type zeolite subjected to the copper ion exchange are copper monovalent sites, and / or at least 60% or more of the copper monovalent sites. The gas adsorbent characterized by being a trivalent oxygen monovalent copper site can adsorb and immobilize a larger amount of moisture and oxygen. Moreover, stronger gas adsorption is possible. As a result, it is possible to provide a high-performance display device that can adsorb and immobilize a larger amount of moisture and oxygen more strongly than existing gas adsorbents and is excellent in reliability.

  In the adsorbent comprising ZSM-5 type zeolite subjected to copper ion exchange according to the present embodiment, the moisture adsorption property under low pressure is changed by changing the kind and concentration of the ion exchange solution containing copper ions and ions having a buffer action. The results of evaluation are shown in Example 1 to Example 4. In Example 1, the result of the oxygen adsorption amount is also shown.

  The amount of adsorbed water and the amount of oxygen were measured with an adsorption capacity measuring device BELSORP-18PLUS.

  The silica-alumina ratio of the ZSM-5 type zeolite used was 11.9, and the heat treatment was performed at 600 ° C. for 4 hours.

Example 1
In order to prepare an ion exchange solution containing copper ions and ions having a buffer action, copper acetate and ammonium acetate were used. Each concentration is 0.03M copper acetate and 0.03M ammonium acetate, and each is subjected to ion exchange five times at room temperature using a solution in which each is mixed at a ratio of 1: 0.1. A copper ion exchanged ZSM-5 type zeolite was prepared.

After the heat treatment, the sample was cooled to 25 ° C. and the adsorption characteristics were evaluated. As a result, the moisture adsorption amount was 14.0 cc / g at 1320 Pa, 12.1 cc / g at 10 Pa, and 1.0 cc / g at 10 ⁻² Pa. The oxygen adsorption amount was 14.2 cc / g at 1320 Pa, 8.8 cc / g at 10 Pa, and 0.9 cc / g at 10 ⁻² Pa.

  These results indicate the amount of adsorption that has reached the adsorption equilibrium under each pressure, and are considered to correspond to the amount of adsorption at the corresponding partial pressure.

  Among the copper sites of the ZSM-5 type zeolite subjected to copper ion exchange in this example, the copper monovalent site is 91%, and among the copper monovalent sites, the oxygen tricoordinate copper monovalent site is 83%. The ion exchange rate was 130%.

Compared with Comparative Examples 1 to 3, increases in the moisture and oxygen adsorption amounts are observed, and the difference is particularly remarkable under the ^10-2 Pa condition. Moreover, the volume expansion accompanying adsorption | suction hardly occurred. Therefore, it is excellent in the ability to adsorb and remove moisture and oxygen in the display device as compared with conventional adsorbents.

  This is due to the increase in the copper monovalent sites and the oxygen tricoordinate copper monovalent sites.

(Example 2)
In order to prepare an ion exchange solution containing copper ions and ions having a buffer action, copper acetate and ammonium acetate were used. Each concentration is 0.01M copper acetate and 0.01M ammonium acetate, and each is subjected to ion exchange five times at room temperature using a solution in which each is mixed at a ratio of 1: 0.1. A copper ion exchanged ZSM-5 type zeolite was prepared.

After the heat treatment, it was cooled to 25 ° C. and the adsorption characteristics were evaluated. As a result, the moisture adsorption amount was 12.8 cc / g at 1320 Pa, 8.1 cc / g at 10 Pa, and 0.8 cc / g at 10 ⁻² Pa.

  In this example, among the copper sites of the ZSM-5 type zeolite subjected to the copper ion exchange, the copper monovalent site is 75%, and among the copper monovalent sites, the oxygen tricoordinate copper monovalent site is 82. The ion exchange rate was 125%.

Compared with Comparative Examples 1 to 3, increases in the moisture and oxygen adsorption amounts are observed, and the difference is particularly remarkable under the ^10-2 Pa condition. Therefore, it is excellent in the ability to adsorb and remove moisture and oxygen in the display device as compared with conventional adsorbents.

  This is due to the increase in the copper monovalent sites and the oxygen tricoordinate copper monovalent sites.

(Example 3)
In order to prepare an ion exchange solution containing copper ions and ions having a buffer action, copper acetate and sodium acetate were used. Each concentration is 0.03M for copper acetate and 0.03M for sodium acetate, and each is subjected to ion exchange five times at room temperature using a solution in which each is mixed at a ratio of 1: 0.1. A copper ion exchanged ZSM-5 type zeolite was prepared.

When the adsorption property was evaluated after cooling to 25 ° C. after heat treatment, the moisture adsorption amount was 9.8 cc / g at 1320 Pa, 6.0 cc / g at 10 Pa, and 0.50 cc / g at 10 ⁻² Pa.

  In this example, among the copper sites of the ZSM-5 type zeolite subjected to the copper ion exchange, the copper monovalent site is 70%, and among the copper monovalent sites, the oxygen tricoordinate copper monovalent site is 70%. The ion exchange rate was 117%.

Compared with Comparative Examples 1 to 3, increases in the moisture and oxygen adsorption amounts are observed, and the difference is particularly remarkable under the ^10-2 Pa condition. Moreover, the volume expansion accompanying adsorption | suction hardly occurred. Therefore, it is excellent in the ability to adsorb and remove moisture and oxygen in the display device as compared with conventional adsorbents.

  This is due to the increase in the copper monovalent sites and the oxygen tricoordinate copper monovalent sites.

  On the other hand, the amount of adsorption is lower than in Examples 1 and 2. This is considered to be because ions having a buffering action are generated from sodium acetate.

Example 4
Copper acetate was used to prepare an ion exchange solution containing copper ions. The copper acetate concentration was 0.03M, and ion exchange was performed 5 times at room temperature to prepare ZSM-5 type zeolite subjected to copper ion exchange.

After the heat treatment, it was cooled to 25 ° C. and the adsorption characteristics were evaluated. As a result, the moisture adsorption amount was 6.6 cc / g at 1320 Pa, 4.6 cc / g at 10 Pa, and 0.12 cc / g at 10 ⁻² Pa.

  In this example, among the copper sites of the ZSM-5 type zeolite subjected to the copper ion exchange, the copper monovalent site is 62%, and among the copper monovalent sites, the oxygen tricoordinate copper monovalent site is It was 64%. The ion exchange rate was 109%.

Compared with Comparative Examples 1 to 3, increases in the moisture and oxygen adsorption amounts are observed, and the difference is particularly remarkable under the ^10-2 Pa condition. Moreover, the volume expansion accompanying adsorption | suction hardly occurred. Therefore, it is excellent in the ability to adsorb and remove moisture and oxygen in the display device as compared with conventional adsorbents.

(Embodiment 2)
FIG. 2 is a cross-sectional view showing an organic electroluminescence element of a display device including a gas adsorbent containing ZSM-5 type zeolite subjected to copper ion exchange in Embodiment 2 of the present invention.

  The organic electroluminescence member 5 is formed on a substrate 6 and sealed with a sealing member 7, and a gas adsorbent 8 containing at least copper ion-exchanged ZSM-5 type zeolite is formed on the upper inner surface of the sealing member 7. Is installed. The substrate 6 and the sealing member 7 are fixed with an adhesive or the like that hardly allows moisture and oxygen to pass therethrough.

  The gas adsorbing material 4 is installed by a method of installing the gas adsorbing material 4 in the sealed space, such as sticking with an adhesive material or double-sided tape, or fixing the gas adsorbing material 4 with a projection formed on the inner surface. If so, it can be used without any special specification.

  With this configuration, at the time of manufacturing the display device, the gas adsorbent 4 immobilizes and removes the residual moisture and oxygen in the inert gas sealed in the sealed space to a low partial pressure. Further, during the operation of the display device, moisture and oxygen entering from the outside over time reach the gas adsorbent 4 and are adsorbed.

  As a result, it is possible to more strongly adsorb and immobilize moisture and oxygen of a larger volume under a lower partial pressure than existing gas adsorbents, and to peel off the interface between the electrode and the light emitting layer, to increase resistance by oxidizing the electrode, Alternatively, deterioration of the light emitting layer itself can be prevented, luminance and uniformity of light emission can be maintained, and long-life and reliable display quality can be obtained.

  As described above, in this embodiment, it is possible to stably realize excellent display device performance over a long period of time.

  Next, comparative examples for the present invention will be shown. The evaluation method shall be in accordance with the example.

(Comparative Example 1)
When the moisture adsorption property of barium oxide, which has been disclosed as having hygroscopicity, was evaluated, the moisture adsorption amount was 4.0 cc / g at 1320 Pa, 1.1 cc / g at 10 Pa, and 0.0 cc / at 10 ⁻² Pa. g. Although the adsorption amount near atmospheric pressure is excellent, it can be seen that the adsorption amount in the low partial pressure region is relatively small. Further, volume expansion due to moisture adsorption was confirmed.

  It was also confirmed that oxygen adsorption was impossible.

(Comparative Example 2)
When the moisture adsorption property of calcium oxide, which has been disclosed as having hygroscopicity, was evaluated, the moisture adsorption amount was 5.1 cc / g at 1320 Pa, 2.0 cc / g at 10 Pa, and 0.1 cc / at 10 ⁻² Pa. g. It is excellent in the amount of adsorption near atmospheric pressure, and the amount of adsorption in the low partial pressure region is larger than that in Comparative Example 1, but is smaller than that in Examples of the present invention. Further, volume expansion due to moisture adsorption was confirmed.

  It was also confirmed that oxygen adsorption was impossible.

(Comparative Example 3)
When the moisture adsorption property of zeolite 4A, which has been disclosed as having hygroscopic properties, was evaluated, the moisture adsorption amount was 4.1 cc / g at 1320 Pa, 0.0 cc / g at 10 Pa, and 0.0 cc / at 10 ⁻² Pa. g. The oxygen adsorption amount was 0.8 cc / g at 1320 Pa, 0.0 cc / g at 10 Pa, and 0.0 cc / g at 10 ⁻² Pa.

  Although it has been confirmed that the amount of adsorption near atmospheric pressure is excellent, it can be seen that it is inappropriate for adsorption in a low partial pressure region. There was no volume expansion due to moisture adsorption.

  The gas adsorbent containing the ZSM-5 type zeolite subjected to the copper ion exchange is divided into components such as low partial pressure moisture and oxygen remaining in the inert gas and moisture and oxygen entering the sealed space over time. High ability to adsorb and fix even under low pressure. Therefore, it is possible to more strongly adsorb and immobilize a larger volume of moisture and oxygen at a lower partial pressure than existing gas adsorbents, peel off the interface between the electrode and the light emitting layer, increase the resistance by oxidizing the electrode, or emit light. It becomes possible to prevent deterioration of the layer itself, and to maintain the luminance and uniformity of light emission and to obtain a long-life and reliable display quality.

The flowchart which shows the manufacturing method of the gas adsorbent containing the ZSM-5 type zeolite by which the copper ion exchange in Embodiment 1 of this invention was carried out Sectional drawing of the electroluminescent element of the display apparatus in Embodiment 2 of this invention

Explanation of symbols

5 Organic electroluminescence member 8 Gas adsorbent

Claims (6)

  A display device comprising a gas adsorbent containing at least a copper ion exchanged ZSM-5 type zeolite in a sealed space in which an organic electroluminescence member is sealed.   2. The display device according to claim 1, wherein at least 60% or more of copper sites of the ZSM-5 type zeolite subjected to copper ion exchange are copper monovalent sites.   3. The display device according to claim 1, wherein at least 60% or more of the copper monovalent sites are oxygen tricoordinate copper monovalent sites. 4.   The copper ion-exchanged ZSM-5 type zeolite is ion-exchanged with an ion-exchange solution containing at least copper ions and ions having a buffer action. The display device described in 1.   The display device according to claim 4, wherein the ions having a buffer action are acetate ions.   6. The display device according to claim 4, wherein the ions having a buffering action are generated from ammonium acetate.